The swing mechanisms for tractor booms, such as backhoe booms, are controlled by valves or switch means which, in some cases, are actuated by a pair of foot-operated pedals. Such pedals are typically on either side of a vertical housing structure which contains various control rods and linkages related to various boom and tool movements.
The pedals are each pivotably mounted with respect to a tractor upright, which is usually part of the vertical structure. Control linkages typically extend from a shaft affixed to a pedal toward the appropriate valve or switch which swings the boom to the right or to the left.
The operator usually sits on a seat facing and somewhat straddling such vertical structure with one foot on each of the two pedals. Depressing the right pedal causes the boom to swing to the right, while depressing the left pedal causes the boom to swing to the left. Various mechanical linkages typically cause the pedal not being depressed to move upward while the other pedal is depressed.
Since operators of different sizes and physical characteristics operate the equipment, the orientation or position of the foot pedals with respect to the seat frequently is improper for the person operating the equipment. For example, a short operator may have difficulty properly engaging both pedals with his feet unless he slides forward on the seat. Even then, the angle of the pedals may not be comfortable for him. Long-legged operators have the same sorts of problems related to ease of use and comfort during use.
Furthermore, any operator using the equipment over a long work shift may find it uncomfortable to maintain his legs, feet and other parts of his body in the same orientation hour after hour. Periodic adjustment is considered desirable over such long periods of time.
In the past, tractor boom swing control pedals have been adjusted by adjusting the length of control rods which are typically inside the vertical structure. Such adjustments may be difficult because of the relative inaccessibility of such control rods and sometimes because of the nature of the control rod interconnections. Other adjustment concepts, such a placing blocks on the pedals, are considered undesirable since they tend to make operation of the swing control pedals more difficult.
There has been a need for an improved two-pedal swing control apparatus which may readily be adjusted to position the pedals to accommodate different operators, and to change the body and leg orientations of an operator from time to time.